Turkey's S-400 purchase not in NATO's interest, says Mattis

At the US House Committee for Armed Services hearing of 12 April, Secretary of Defense Jim Mattis stated that Turkey's acquisition of Russian-made S-400 air-defence system works against NATO's interests, adding that US is negotiating with Turkey a possible counter-offer, although Ankara's deal with Moscow seems sealed.

Mattis' remarks are a reiteration of the US position vis-a-vis the deal so far, as although Washington previously recognised Turkey's sovereign right to chose an air-defence system, it warned that the S-400 will never be interoperable with NATO systems, thus creating additional vulnerabilities for the alliance. Since February 2018, reports have been circulating about possible US sanctions against Turkey under the Countering America’s Adversaries Through Sanctions Act which gives President Trump the power to cut off all arms sales to regimes doing business with blacklisted entities, such as the Russian Rosoboronexport. In spite of its increasingly cool relations with Western powers, due to issues ranging from its stance on Syria to regime's curtailing of civil liberties and crackdown on Kurds and political opponents, Turkey maintains the deal with Russia has no political motive, and is only a temporary solution until it can build an air-defence system of its own, an option it is jointly exploring with Eurosam.